DisastersMegastorm could devastate California, not just earthquakes
A team of over 100 scientists, engineers, and emergency planners are urging California disaster planning officials to prepare for megastorms; the team projected that a catastrophic megastorm could decimate California with massive landslides and flooding; the findings were based on geological evidence of such powerful storms that occur every 300 years; the last megastorm occurred in 1861 and left the Sacramento Valley an “inland sea”
The superstorm looms that could devestate California // Source: coudynews.com
A team of more thatn 100 scientists, engineers, and emergency planners projected that a catastrophic “megastorm” could decimate California by triggering massive landslides and floods that could damage 25 percent of homes in the state.
The team used flood mapping, climate change projections, and geologic flood history to simulate a hypothetical storm so intense it only occurs every 100 to 200 years.
The team’s simulation was based on California’s most severe weather event – a forty-five day long series of storms in 1861 that caused so much flooding that according to the U.S. Geological Survey (USGS) the Sacramento Valley became “an inland sea.”
The damage was so extensive that the state Capitol had to be moved from Sacramento to San Francisco and then “Governor Leland Stanford was forced to take a rowboat to his inauguration.”
Geologists uncovered evidence of even larger storms that occurred every 300 years and fear that storms of that magnitude could become more frequent and powerful due to global warming.
The study was not meant to be a prediction of an imminent threat, but rather a move to raise awareness about a threat disaster planning officials were not anticipating in California.
California emergency response officials have devoted much of their attention to preparing for earthquakes and have not paid as much attention to mitigating damage from powerful winter storms.
Scientists are particularly concerned because unlike an earthquake that is confined to a geographic location, a megastorm could wreak havoc on the entire state.
Lucy Jones, chief scientist at the USGS’ Multi-Hazards Project says, “We need to recognize that flooding here in California is as much of a risk as an earthquake.”
“These storms are like hurricanes in the amount of rain that they produce,” Jones added.
Mark Jackson, the head meteorologist at the National Weather Service in Oxnard, California, confirms Jones assessment.
According to Jackson, “It’s an extreme but plausible storm.”
“Our landscape can really handle quite a bit of rain. But when you get two storms back to back, you reach saturation, and the flood control systems are pushed over capacity,” he said.
The study identified the most vulnerable areas that would be hardest hit in such a megastorm.
The greater Los Angeles area, the San Francisco Bay Area, and San Diego would be the most susceptible to floodwaters from overflowing rivers. Further inland, 300 miles of the Central Valley would be completely submerged destroying crops, wiping out livestock, and damaging structures.
The state’s infrastructure would also be overwhelmed in such a scenario with water overpowering the state’s flood protection system. In particular, the levees holding back the Sacramento-San Joaquin River Delta, which provides 76 percent of the state’s fresh water supply, would burst as they are not capable of withstanding such a storm.
Finally landslides would ruin roads and railroad lines while flooding would damage water and sewer lines disrupting utilities for months.
The findings were presented at a conference to officials from the USGS, the Federal Emergency Management Agency (FEMA), and the California Emergency Management Agency.
